German scientists have developed a textile finish that provides a sensory cooling effect. The textile finish is based on p-menthane derivatives (agonists) such as WS-3 (N-ethyl-p-menthane-3-carboxamide) or L-menthyl lactate and icilin. These substances have the advantage when spread in low concentrations on small areas of the body, they have a lasting and mild cooling effect.
Sensory cooling is the term used to describe a chemically induced sensation of coolness on the skin, due to the triggering of cold receptors at the nerve ends close to the surface of the skin. This is different from the cooling effect normally achieved by physical processes where the skin is cooled mainly by the evaporation of water.
Unlike conventional cooling methods, cold-inducing substances that result in sensory cooling have a mild cooling effect, even when spread over a large area, without over-cooling the skin. One example of this would be the peppermint substance menthol. This has a cooling effect and soothes itching.
Sensory cooling textiles are effective in textiles worn close to the skin, but are unsuitable for loosely cut clothing that is not in direct contact with the body. The sensory perception of cold depends not only on the area of the skin being treated but also on a range of other parameters such as the moisture level in the skin and the topography of the skin surface.